diff --git a/locales/rn/en.json b/locales/rn/en.json
index 439b081f..a569206a 100644
--- a/locales/rn/en.json
+++ b/locales/rn/en.json
@@ -417,6 +417,7 @@
     "delete_item_title": "Delete this item?",
     "delete_items_title": "{count, plural, one {Delete # item?} other {Delete # items?}}",
     "done": "Done",
+    "download_failed_status": "Download failed (HTTP {status})",
     "folder_empty": "This folder is empty",
     "invalid_name": "Invalid name",
     "invalid_name_slash": "Names cannot contain \"/\".",
diff --git a/src/components/__tests__/contacts-i18n.test.ts b/src/components/__tests__/contacts-i18n.test.ts
index aa2818d7..833e27f6 100644
--- a/src/components/__tests__/contacts-i18n.test.ts
+++ b/src/components/__tests__/contacts-i18n.test.ts
@@ -25,6 +25,7 @@ const TRANSLATED_FILES: Record<string, string[]> = {
   'components/contacts/ContactPickerSheet.tsx': [],
   'components/contacts/TagAssignSheet.tsx': [],
   'components/contacts/ContactListRow.tsx': [],
+  'components/contacts/FieldBlock.tsx': [],
 };
 
 describe('translated contacts screens', () => {
diff --git a/src/components/calendar/EventCard.tsx b/src/components/calendar/EventCard.tsx
index a67606b3..ddc71ce0 100644
--- a/src/components/calendar/EventCard.tsx
+++ b/src/components/calendar/EventCard.tsx
@@ -80,7 +80,7 @@ export function EventCard({ event, calendars, timeFormat, onPress, onLongPress }
           <View style={styles.detailRow}>
             <Users size={12} color={c.textMuted} />
             <Text style={styles.detailText}>
-              {count} {t('calendar.participants.title', 'Participants').toLowerCase()}
+              {t('calendar.participants.count', '{count, plural, one {# participant} other {# participants}}', { count })}
             </Text>
           </View>
         )}
diff --git a/src/components/calendar/EventDetailSheet.tsx b/src/components/calendar/EventDetailSheet.tsx
index 7c43b1ed..0429e54e 100644
--- a/src/components/calendar/EventDetailSheet.tsx
+++ b/src/components/calendar/EventDetailSheet.tsx
@@ -340,7 +340,7 @@ export function EventDetailSheet({
                 <View style={styles.participantsHeader}>
                   <Users size={16} color={c.textMuted} />
                   <Text style={styles.participantsHeaderText}>
-                    {participants.length} {t('calendar.participants.title', 'Participants').toLowerCase()}
+                    {t('calendar.participants.count', '{count, plural, one {# participant} other {# participants}}', { count: participants.length })}
                   </Text>
                 </View>
                 {participants.map((p) => (
diff --git a/src/components/contacts/ContactActivity.tsx b/src/components/contacts/ContactActivity.tsx
index 6a53dc77..b7caf5a9 100644
--- a/src/components/contacts/ContactActivity.tsx
+++ b/src/components/contacts/ContactActivity.tsx
@@ -3,7 +3,7 @@ import { ActivityIndicator, Pressable, StyleSheet, Text, View } from 'react-nati
 import { useNavigation } from '@react-navigation/native';
 import type { NativeStackNavigationProp } from '@react-navigation/native-stack';
 import { Mail as MailIcon, CalendarDays } from 'lucide-react-native';
-import { format, isAfter, parseISO } from 'date-fns';
+import { format, isAfter, parseISO, type Locale } from 'date-fns';
 import type { ContactCard, Email, CalendarEvent } from '../../api/types';
 import type { RootStackParamList } from '../../navigation/types';
 import { getEmails, queryEmailsByFilter } from '../../api/email';
@@ -11,6 +11,7 @@ import { getEvents, queryEvents } from '../../api/calendar';
 import { useCalendarStore } from '../../stores/calendar-store';
 import { useLocaleStore, type TranslateFn } from '../../stores/locale-store';
 import { getEventColor } from '../../lib/calendar-utils';
+import { getDateFnsLocale } from '../../lib/calendar-locale';
 import { hasCalendarCapability } from '../../lib/capabilities';
 import { singleLine } from '../../lib/single-line';
 import { prefetchMessage } from '../../lib/email-detail-cache';
@@ -64,13 +65,13 @@ function eventInvolvesContact(event: CalendarEvent, addresses: Set<string>): boo
   return false;
 }
 
-function formatRelativeDate(iso: string): string {
+function formatRelativeDate(iso: string, locale: Locale): string {
   try {
     const d = parseISO(iso);
     const now = new Date();
     return d.getFullYear() === now.getFullYear()
-      ? format(d, 'MMM d')
-      : format(d, 'MMM d, yyyy');
+      ? format(d, 'MMM d', { locale })
+      : format(d, 'MMM d, yyyy', { locale });
   } catch {
     return '';
   }
@@ -94,6 +95,7 @@ export function ContactActivity({ contact }: Props) {
   const styles = React.useMemo(() => makeStyles(c), [c]);
   const navigation = useNavigation<Nav>();
   const t = useLocaleStore((s) => s.t);
+  const dateLocale = getDateFnsLocale(useLocaleStore((s) => s.locale));
   const calendarEvents = useCalendarStore((s) => s.events);
   const calendars = useCalendarStore((s) => s.calendars);
 
@@ -222,7 +224,7 @@ export function ContactActivity({ contact }: Props) {
                   <View style={styles.rowContent}>
                     <View style={styles.rowTop}>
                       <Text style={styles.rowSender} numberOfLines={1}>{senderName}</Text>
-                      <Text style={styles.rowDate}>{formatRelativeDate(email.receivedAt)}</Text>
+                      <Text style={styles.rowDate}>{formatRelativeDate(email.receivedAt, dateLocale)}</Text>
                     </View>
                     <Text style={styles.rowSubject} numberOfLines={1}>
                       {singleLine(email.subject) || t('contacts.activity.no_subject', '(No subject)')}
@@ -260,7 +262,7 @@ export function ContactActivity({ contact }: Props) {
                     {event.title || t('contacts.activity.no_title', '(No title)')}
                   </Text>
                   <Text style={styles.eventDate}>
-                    {formatRelativeDate(event.utcStart || event.start)}
+                    {formatRelativeDate(event.utcStart || event.start, dateLocale)}
                   </Text>
                 </View>
               </View>
diff --git a/src/components/contacts/FieldBlock.tsx b/src/components/contacts/FieldBlock.tsx
index 632d2da5..723af526 100644
--- a/src/components/contacts/FieldBlock.tsx
+++ b/src/components/contacts/FieldBlock.tsx
@@ -3,6 +3,7 @@ import { View, Text, StyleSheet, Pressable } from 'react-native';
 import { Plus, X } from 'lucide-react-native';
 import { spacing, radius, typography, type ThemePalette } from '../../theme/tokens';
 import { useColors } from '../../theme/colors';
+import { useLocaleStore } from '../../stores/locale-store';
 
 export type CategoryAccent = 'contact' | 'work' | 'location' | 'personal' | 'digital' | 'calendar' | 'notes';
 
@@ -59,11 +60,18 @@ interface FieldRowProps {
 export function FieldRow({ onRemove, children }: FieldRowProps) {
   const c = useColors();
   const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
   return (
     <View style={styles.row}>
       <View style={{ flex: 1 }}>{children}</View>
       {onRemove && (
-        <Pressable onPress={onRemove} hitSlop={8} style={styles.removeBtn}>
+        <Pressable
+          onPress={onRemove}
+          hitSlop={8}
+          style={styles.removeBtn}
+          accessibilityRole="button"
+          accessibilityLabel={t('common.remove', 'Remove')}
+        >
           <X size={14} color={c.textMuted} />
         </Pressable>
       )}
diff --git a/src/components/settings/FilterSettings.tsx b/src/components/settings/FilterSettings.tsx
index 9e1339c8..b0bcf397 100644
--- a/src/components/settings/FilterSettings.tsx
+++ b/src/components/settings/FilterSettings.tsx
@@ -354,7 +354,11 @@ export function FilterSettings({ onOpenVacation }: FilterSettingsProps = {}) {
               const editIdx = editableIds.indexOf(rule.id);
 
               if (readonly) {
-                const label = rule.originLabel || t('settings.filters.origin_external', 'External');
+                // The parser names known tools (product names) and falls back
+                // to "External", which is shown in the app language.
+                const label = rule.originLabel && rule.originLabel !== 'External'
+                  ? rule.originLabel
+                  : t('settings.filters.origin_external', 'External');
                 const hasStructured = rule.origin === 'external' && rule.conditions.length > 0 && rule.actions.length > 0;
                 return (
                   <View key={rule.id} style={styles.ruleRow}>
diff --git a/src/components/settings/VacationSettings.tsx b/src/components/settings/VacationSettings.tsx
index e9382d08..e9ab2e11 100644
--- a/src/components/settings/VacationSettings.tsx
+++ b/src/components/settings/VacationSettings.tsx
@@ -278,10 +278,10 @@ export function VacationSettings() {
         {htmlEnabled && (
           <View style={styles.editorBlock}>
             <View style={styles.editorToolbar}>
-              <ToolbarButton c={c} onPress={() => editorRef.current?.exec('bold')}><Bold size={16} color={c.text} /></ToolbarButton>
-              <ToolbarButton c={c} onPress={() => editorRef.current?.exec('italic')}><Italic size={16} color={c.text} /></ToolbarButton>
-              <ToolbarButton c={c} onPress={() => editorRef.current?.exec('underline')}><Underline size={16} color={c.text} /></ToolbarButton>
-              <ToolbarButton c={c} onPress={() => editorRef.current?.exec('insertUnorderedList')}><ListIcon size={16} color={c.text} /></ToolbarButton>
+              <ToolbarButton c={c} label={t('email_composer.toolbar.bold', 'Bold')} onPress={() => editorRef.current?.exec('bold')}><Bold size={16} color={c.text} /></ToolbarButton>
+              <ToolbarButton c={c} label={t('email_composer.toolbar.italic', 'Italic')} onPress={() => editorRef.current?.exec('italic')}><Italic size={16} color={c.text} /></ToolbarButton>
+              <ToolbarButton c={c} label={t('email_composer.toolbar.underline', 'Underline')} onPress={() => editorRef.current?.exec('underline')}><Underline size={16} color={c.text} /></ToolbarButton>
+              <ToolbarButton c={c} label={t('email_composer.toolbar.bullet_list', 'Bullet list')} onPress={() => editorRef.current?.exec('insertUnorderedList')}><ListIcon size={16} color={c.text} /></ToolbarButton>
             </View>
             <View style={styles.editorFrame}>
               <RichTextEditor
@@ -359,11 +359,15 @@ export function VacationSettings() {
   );
 }
 
-function ToolbarButton({ c, onPress, children }: { c: ThemePalette; onPress: () => void; children: React.ReactNode }) {
+function ToolbarButton({
+  c, label, onPress, children,
+}: { c: ThemePalette; label: string; onPress: () => void; children: React.ReactNode }) {
   return (
     <Pressable
       onPress={onPress}
       hitSlop={6}
+      accessibilityRole="button"
+      accessibilityLabel={label}
       style={({ pressed }) => ({
         width: 32, height: 32, borderRadius: radius.sm,
         alignItems: 'center', justifyContent: 'center',
diff --git a/src/lib/email-export.ts b/src/lib/email-export.ts
index ae06ff02..04fd9768 100644
--- a/src/lib/email-export.ts
+++ b/src/lib/email-export.ts
@@ -6,6 +6,7 @@ import { jmapClient } from '../api/jmap-client';
 import { getDownloadUrl, isStaleUploadCopy } from '../api/blob';
 import type { Attachment, Email } from '../api/types';
 import { useSettingsStore } from '../stores/settings-store';
+import { t } from '../stores/locale-store';
 import {
   attachmentDownloadFilename,
   emailExportFilename,
@@ -197,7 +198,7 @@ async function downloadInto(
       headers: { Authorization: jmapClient.authHeader },
     });
     if (!response.ok) {
-      throw new Error(`Download failed: ${response.status}`);
+      throw new Error(t('files.download_failed_status', 'Download failed (HTTP {status})', { status: response.status }));
     }
     if (dest.exists) dest.delete();
     const buffer = await response.arrayBuffer();
@@ -249,7 +250,7 @@ export async function shareAttachment(
     return;
   }
   if (!(await Sharing.isAvailableAsync())) {
-    throw new Error('Sharing is not available on this device');
+    throw new Error(t('files.share_unavailable', 'Sharing is not available on this device'));
   }
   try {
     await Sharing.shareAsync(downloaded.uri, {
@@ -287,7 +288,7 @@ export async function downloadAttachment(
 
 async function offerSavedFile(file: File, filename: string, mimeType: string): Promise<void> {
   if (!(await Sharing.isAvailableAsync())) {
-    throw new Error('Sharing is not available on this device');
+    throw new Error(t('files.share_unavailable', 'Sharing is not available on this device'));
   }
   await Sharing.shareAsync(file.uri, {
     mimeType,
@@ -399,7 +400,7 @@ export async function shareLocalFile(
 ): Promise<void> {
   if (!opts.forceSheet && Platform.OS === 'android' && (await openWithViewer(file, mimeType))) return;
   if (!(await Sharing.isAvailableAsync())) {
-    throw new Error('Sharing is not available on this device');
+    throw new Error(t('files.share_unavailable', 'Sharing is not available on this device'));
   }
   try {
     await Sharing.shareAsync(file.uri, { mimeType, dialogTitle: dialogTitle ?? file.name });
@@ -441,7 +442,7 @@ async function authedBlobFetch(url: string): Promise<Response> {
   if (r.status === 401 && (await jmapClient.forceRefreshToken())) {
     r = await secureFetch(url, { headers: { Authorization: jmapClient.authHeader } });
   }
-  if (!r.ok) throw new Error(`Download failed: ${r.status}`);
+  if (!r.ok) throw new Error(t('files.download_failed_status', 'Download failed (HTTP {status})', { status: r.status }));
   return r;
 }
 
@@ -534,7 +535,7 @@ export async function shareEmailEml(
     : safeFilename(subjectFallback);
   const downloaded = await cacheBlobFile(blobId, filename, RFC822, accountId);
   if (!(await Sharing.isAvailableAsync())) {
-    throw new Error('Sharing is not available on this device');
+    throw new Error(t('files.share_unavailable', 'Sharing is not available on this device'));
   }
   try {
     await Sharing.shareAsync(downloaded.uri, {